title: Preventive treatment of ectopically erupting maxillary permanent canines by extraction of deciduous canines and first molars: A randomized clinical trial.
abstract: BACKGROUND
  In this research project, we aimed to compare the effectiveness of single (1 deciduous canine) and double (deciduous canine and first molar) extractions in subjects with retained maxillary permanent canines positioned palatally or centrally in the alveolar crest, at risk for root resorption of adjacent permanent teeth.
  
  
  METHODS
  Subjects at risk for canine impaction or resorptive situations were randomly assigned to 1 of 2 treatment modalities: single extraction (17 patients, 28 canines) or double extraction (20 patients, 37 canines). Thirty-one patients with 53 canines judged to be not at risk constituted the untreated control group. Panoramic radiographs were taken at the initial observation and after 18 months on average. Between-group statistical comparisons were carried out on the changes in canine inclination and sector location (measured on panoramic radiographs) and on the percentages of successful permanent canine eruptions.
  
  
  RESULTS
  The double-extraction group showed significant improvements in the success rate and the intrabony position of the permanent canine, in terms of uprighting the canine's long axis with a crown movement in a distal direction.
  
  
  CONCLUSIONS
  Concomitant deciduous canine and first molar extractions proved to be more effective as a preventive approach to promote eruption of retained maxillary permanent canines positioned palatally or centrally.
authors.affiliation: Department of Orthodontics, Alma Mater Studiorum University of Bologna, Bologna, Italy. giulio.alessandri@unibo.it
authors.forename: Giulio
authors.initials: G
authors.lastname: Alessandri Bonetti
authors.forename: Matteo
authors.initials: M
authors.lastname: Zanarini
authors.forename: Serena
authors.initials: S
authors.lastname: Incerti Parenti
authors.forename: Ida
authors.initials: I
authors.lastname: Marini
authors.forename: Maria Rosaria
authors.initials: MR
authors.lastname: Gatto
mesh_terms: D000293:Adolescent; D002648:Child; D003481:Cuspid / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008437:Maxilla / Q000473:pathology*; D008963:Molar / Q000601:surgery*; D009805:Odontogenesis / Q000502:physiology; D011862:Radiography, Panoramic; D012307:Risk Factors; D012391:Root Resorption / Q000517:prevention & control; D019228:Tooth Crown / Q000000981:diagnostic imaging; D014079:Tooth Eruption, Ectopic / Q000517:prevention & control*; D014081:Tooth Extraction; D014092:Tooth Root / Q000000981:diagnostic imaging; D014094:Tooth, Deciduous / Q000601:surgery*; D016896:Treatment Outcome